Apple has finally released the public version of iOS 9.2 with major bug fixes and some new features. One the feature of iOS 9.2 is to let you import photos and videos directly from an external USB source. There are specific users who are still happy with iOS 9.1 and have updated to iOS 9.2 either accidentally or for experiment purpose.
In case you have updated to latest iOS and wish to revert back to iOS 9.1, then you still have the signing window open from Apple. There is no surety how long apple will be signing the iOS 9.1 IPSW, so if you are planning to downgrade, you'll need to act quickly. Below guide shows the process of downgrading to iOS 9.1.
How to Downgrade from iOS 9.2 to iOS 9.1 on iPhone and iPad
Step #1: First and foremost thing you will need is the correct IPSW file for your iDevice. Get it from here, but make sure you download the correct IPSW file for your firmware.
Step #2: There isn’t any risk involved, but precautions are better than to cure. So completely backup your device with iTunes or iCloud.
Step #3: Open iTunes while your device connected with USB cable.
Step #4: Now select your device and OPTION + Click on “Restore iPhone“. If you are a Windows user, you'll have to SHIFT + Click on “Restore iPhone” button.
Step #5: Now select the IPSW file from the destination folder, which you downloaded it in the first step.
Step #6: The downgrade process will take few minutes, so have patience while it is finished.
Once the process is finished, you will have two options: either to setup your device as new or restore from the backup you took earlier.
That's all; you are now on iOS 9.1. However, we wouldn't recommend downgrading because iOS 9.2 has major bug fixes and some really exciting new features. Did you downgrade to iOS 9.1? If yes, share with us the reason for downgrading in comment, on Facebook, Twitter and Google Plus.